x86/vector/msi: Select CONFIG_GENERIC_IRQ_RESERVATION_MODE

Select CONFIG_GENERIC_IRQ_RESERVATION_MODE so PCI/MSI domains get the
MSI_FLAG_MUST_REACTIVATE flag set in pci_msi_create_irq_domain().

Remove the explicit setters of this flag in the apic/msi code as they are
not longer required.

Fixes: 4900be83 ("x86/vector/msi: Switch to global reservation mode")
Reported-and-tested-by: NDexuan Cui <decui@microsoft.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: Josh Poulson <jopoulso@microsoft.com>
Cc: Mihai Costache <v-micos@microsoft.com>
Cc: Stephen Hemminger <sthemmin@microsoft.com>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: linux-pci@vger.kernel.org
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Simon Xiao <sixiao@microsoft.com>
Cc: Saeed Mahameed <saeedm@mellanox.com>
Cc: Jork Loeser <Jork.Loeser@microsoft.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: devel@linuxdriverproject.org
Cc: KY Srinivasan <kys@microsoft.com>
Link: https://lkml.kernel.org/r/20171017075600.527569354@linutronix.de

arch/x86/Kconfig

@@ -95,6 +95,7 @@ config X86
 	select GENERIC_IRQ_MATRIX_ALLOCATOR	if X86_LOCAL_APIC
 	select GENERIC_IRQ_MIGRATION		if SMP
 	select GENERIC_IRQ_PROBE
+	select GENERIC_IRQ_RESERVATION_MODE
 	select GENERIC_IRQ_SHOW
 	select GENERIC_PENDING_IRQ		if SMP
 	select GENERIC_SMP_IDLE_THREAD

arch/x86/kernel/apic/msi.c

@@ -129,7 +129,7 @@ static struct msi_domain_ops pci_msi_domain_ops = {
 
 static struct msi_domain_info pci_msi_domain_info = {
 	.flags		= MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS |
-			  MSI_FLAG_PCI_MSIX | MSI_FLAG_MUST_REACTIVATE,
+			  MSI_FLAG_PCI_MSIX,
 	.ops		= &pci_msi_domain_ops,
 	.chip		= &pci_msi_controller,
 	.handler	= handle_edge_irq,
@@ -167,8 +167,7 @@ static struct irq_chip pci_msi_ir_controller = {
 
 static struct msi_domain_info pci_msi_ir_domain_info = {
 	.flags		= MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS |
-			  MSI_FLAG_MULTI_PCI_MSI | MSI_FLAG_PCI_MSIX |
-			  MSI_FLAG_MUST_REACTIVATE,
+			  MSI_FLAG_MULTI_PCI_MSI | MSI_FLAG_PCI_MSIX,
 	.ops		= &pci_msi_domain_ops,
 	.chip		= &pci_msi_ir_controller,
 	.handler	= handle_edge_irq,